1. Field of the Invention
The invention relates to an image coding process for the insetting of an imagette into an image coded according to the MPEG standard.
2. Description of Prior Art
Until the last few years, the images produced were generally transmitted and exchanged between television signal broadcasting operators in uncompressed form, that is to say in clear.
When it was necessary to adapt a source programme, the processing of the images was carried out on the basis of professional hardware. For example, when a director needed to utilize a report from a concurrent channel, he could readily, with the aid of a mixer, insert his own logo, information such as subtitles, the score of a match, etc. without additional equipment.
Now that the broadcasting and exchanging of data are performed in the form of compressed data, for example according to the MPEG standard, the insetting techniques require additional hardware: a decoder for bringing the compressed images into baseband at the input of the mixer, a coder for re-encoding the sequences after they have been modified. Moreover, to perform a re-encoding of better quality, it may be necessary to implement a decoder/coder pair which is aware of how to manage assistance information which is added to the coded signal and passes through all the studio equipment before reaching the re-encoder, thereby making the system complex.